1. Field of the Invention
The present invention relates generally to devices for spreading or broadcasting granular material in a uniform manner, more particularly to a grain or silage spreader for distributing grain or silage evenly within a grainery or silo for the proper curing and storage of the material.
2. Description of the Prior Art
The practice of storing grain or silage in enclosed bins is well known in the farming and grain industries. Depositing the grain in a layer of uniform depth in the bin is essential to allow heated air to pass evenly through the grain is desired to effectively dry the grain. To the extent the level of the deposited grain is not uniform throughout, the chances for spoilage increases. Typically, grain or silage is delivered to an opening in the top of the grain bin by an auger or elevator. A grain spreader positioned below the opening in the bin can greatly reduce or eliminate the need for leveling the grain within the bin by hand.
There are many spreaders which attempt to solve this problem. Most of these spreaders have a funnel-shaped hopper and a motor driven thrower plate. Many of these devices throw grain in a single direction at any one instant, theoretically spreading the grain evenly as the plate rotates. However, since it is desirable to load the grain as fast as possible and since it is expensive to elevate the grain any higher than is necessary to inject it through the top of the bin, the grain usually enters the hopper at a rapid rate and at a distinct angle from the vertical. Regardless of how much the grain is slowed down or bounced around by the spreader, some of its entering horizontal momentum resides when it leaves the thrower plate. So long as the spreader is symmetrical in configuration, grain entering at an angle will exit at an angle. Newton's Laws of Motion IV.
Neither of the solutions suggested by the above discussion are practical. To direct the grain into the hopper at a vertical angle, would require that it first be elevated to a considerable additional height for that purpose alone. To shape and size the hopper so that it would temporarily store the grain thus stopping it in transit, and thereby allowing it to drop vertically on to the thrower plate, would require a hopper of huge size in order not to materially slow down the rate of receiving grain.